Peripheral blood haematopoietic progenitor cells in patients with beta thalassaemia major receiving desferrioxamine or deferiprone as chelation therapy

Abstract

Objectives: The main adverse effect of deferiprone is the development of neutropenia, which occurs via an unknown mechanism. We aimed to gain insight into the pathogenesis of deferiprone-induced neutropenia by assessing the peripheral blood haematopoietic progenitor cells.

Methods: Sixteen patients with beta thalassaemia were studied; nine (Group A) were receiving desferrioxamine and seven (Group B) deferiprone. Ten healthy individuals comprised the control group (Group C).

Results: Granulocyte-erythrocyte-monocyte-megakaryocyte colony forming units were significantly more in Groups A and B compared with Group C. Granulocyte-macrophage colony forming units (CFU-GM) were significantly more in Group B compared with Group C. Macrophage colony forming units were significantly less in Group B compared with Group C. Granulocyte colony forming units (CFU-G) were significantly more in Group A compared with Group C. We found a trend in the difference in the number of CFU-G between patients' groups (P = 0.123). Adding serum from patients receiving deferiprone to cultures of controls resulted in a maturation arrest of the granulocytic lineage.

Conclusion: Our findings point to a maturation arrest at the level of CFU-GM as a potential mechanism of deferiprone-induced neutropenia.